urgent help on passing parameters thru ant script

Hi, I am trying to run java code thru junit using ant script. I need to send the authentication information and some other parameters to junit (jvm..) How do i pass a parameter to jvm from ant script.. I read ant manual and i am trying to use <jvmarg> tag to pass parameters but it is not working .. Can any one help me how to pass parameters to JVM thru ant script ... My NumberTest.java file has to access data from database. To access data base I need to send some parameters to Junit JVM like username, password, authentication information file etc ...